RUI: CAS: Alkynyl Complexes of Titanium(IV) and Platinum(II): Phosphors, Photocatalysts, and Fundamental Photophysics

在该RUI项目中，由化学部的化学结构，动力学机制B计划资助，弗曼大学化学系的Paul Wagenknecht教授正在开发新的过渡金属炔基络合物，用作光催化剂和荧光体。 过渡金属光催化剂是有机合成和将太阳能转化为电力和/或化学燃料的系统中的关键组分。 Wagenknecht教授的目标是使用地球上丰富的元素的复合物来取代贵金属光催化剂。 过渡金属荧光粉是有机发光二极管（OLED）的重要组成部分。 Wagenknecht教授的研究小组开发的OLED磷光体涉及一系列旨在增强蓝光发射的复合物，这仍然是一个技术挑战。 这些配合物也显示了发展单组分白色OLED（WOLED）的前景。参与拟议活动的学生将接受与装置化学和太阳能转换为储存化学能直接相关的方法的培训。 这将导致STEM劳动力的发展，准备解决具有严重社会意义的问题。 Wagenknecht教授实验室的学生也积极参与课外辅导计划和/或为当地小学和中学提供化学演示。 他们还积极与高中学生和高中教师开展外联活动。 最近的报道表明，地球上丰富的金属与配体-金属电荷转移激发态的配合物代表了一类新的可能的光催化剂。以前在Wagenknecht教授的实验室开发的二茂钛已被证明是一种可合成的化合物，其激发态氧化还原电位适合用作光催化剂和染料敏化太阳能电池（DSSC）的染料。 提出了具有刚性结构和/或在炔之间配位的Cu（I）的新炔基-二茂钛具有更高的稳定性和更长的激发态寿命，并且将与没有这种修饰的那些进行比较。 这可能会导致对设计第一行过渡金属敏化剂所需的电子物理原理有更强的理解。 Wagenknecht教授的小组开发了一种具有羧酸盐锚定基团的二茂钛前体，以便可以制备一系列二茂钛并将其添加到二氧化钛中，以研究它们在DSSC中作为敏化剂的可能用途并研究电荷注入的原理。 提出的Pt-炔基配合物正在制备的三氟丙炔基配体的蓝移发射，同时保持高的磷光量子产率的作用，机械调查。 此外，蓝色单体发射和橙子准分子发射之间的相互作用将被调查在WOLED器件的可能应用。 该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

In this RUI project, funded by the Chemical Structure, Dynamics & Mechanism B Program of the Chemistry Division, Professor Paul Wagenknecht of the Department of Chemistry at Furman University is developing new transition-metal alkynyl complexes for use as photocatalysts and as phosphors. Transition-metal photocatalysts are crucial components in organic synthesis and in systems for the conversion of solar energy into electricity and/or chemical fuels. Professor Wagenknecht aims to use complexes of earth-abundant elements to replace precious metal photocatalysts. Transition-metal phosphors are essential components of organic light-emitting diodes (OLEDs). The development of phosphors for OLEDs in Professor Wagenknecht’s group involves a set of complexes designed to enhance blue emission, which remains a technical challenge. These complexes also show promise for the development of single-component white OLEDs (WOLEDs). Students involved in the proposed activities will be trained in methods directly related to device chemistry and the conversion of solar energy to stored chemical energy. This will result in the development of a STEM workforce prepared to solve problems of serious social significance. Students in the Professor Wagenknecht’s laboratory are also active in after-hours tutoring programs and/or providing chemistry demonstrations to local elementary and middle schools. They are also active in outreach to high school students and high school teachers. Recent reports demonstrate that complexes of earth-abundant metals with ligand-to-metal charge transfer excited states represent a new class of possible photocatalysts. Titanocenes previously developed in Professor Wagenknecht’s laboratory have proven to be a synthetically accessible class of compounds with excited-state redox potentials appropriate for use as photocatalysts and as dyes for dye-sensitized solar cells (DSSCs). New alkynyl-titanocenes with rigid structures and/or with Cu(I) coordinated between the alkynes are proposed to have higher stability and longer excited-state lifetimes and will be compared to those without such modification. This could lead to a stronger understanding of the photophysical principles necessary to design first-row transition-metal sensitizers. Professor Wagenknecht’s group has developed a titanocene precursor with carboxylate anchoring groups so that a range of titanocenes can be prepared and appended to titanium dioxide to investigate their possible use as sensitizers in DSSCs and investigate principles of charge injection. The Pt-alkynyl complexes proposed are being prepared to mechanistically investigate the role of the trifluoropropynyl ligand in blue-shifting emission while maintaining high phosphorescence quantum yields. Furthermore, the interplay between the blue monomer emission and the orange excimer emission will be investigated for possible applications in WOLED devices. These activities are supported by a robust computational component.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.